Method of making limited stretch bulked yarns



Oct. 14, 1969 METHOD OF MAKING LIMITED STRETCH KIM BULKED YARNS 2 Shets-Sheet 1 INVENTOR. (June/CS (.UJflm BY Oct. 14, 1969 c. w. KIM 3, ,7 7

METHOD OF MAKING LIMITED STRETCH BULKED YARNS Original Filed Nov. 16, 1961 2 Sheets-Sheet Z 9W4 X425 W INVEN 0 I Chan/es United States Patent 3,472,717 METHOD OF MAKING LIMITED STRETCH BULKED YARNS Charles W. Kim, Wilmington, Del., assignor to Joseph Bancroft & Sons Co., Rockford, Wilmington, Del., a corporation of Delaware Original application Nov. 16, 1961, Ser. No. 152,835, now Patent No. 3,276,937, dated Oct. 4, 1966. Divided and this application July 25, 1966, Ser. No. 592,703

Int. Cl. B32b 7/14; D04h 3/08; B29h 9/04 U.S. Cl. 156-148 1 Claim ABSTRACT OF THE DISCLOSURE A crimped yarn is flattened out by being passed over a rotating roll in contact with a low-friction presser element having a heated wire disposed over the center of the flattened yarn. As the yarn is advanced, a thin stripe at the center thereof is heated by the heated wire to a temperature such that the various fibers are bonded together in this narrow stripe only and extend laterally in unbonded condition on opposite sides of the stripe. The bonded stripe limits the stretch characteristics of the yarn and the unbonded fibers on opposite sides of the stripe provide bulk.

This is a division of application Ser. No. 152,835, filed Nov. 16, 1961, now U.S. Patent No. 3,276,937.

This invention relates to the production of a bulked, limited stretch yarn and has for an object to provide a novel and improved method and apparatus for making such a yarn.

More specifically the invention relates to a continuous filament yarn which has been bulked by any well known process as by the use of a stuifer crimper and provides means for imparting limited stretch characteristics to such a yarn.

In accordance with the invention the bulked yarn is first spread out or flattened so that all fibers lie in substantially the same plane and the flattened yarn is then passed through a stage wherein the crossed fibers are joined along one or more longitudinal stripes. The yarn is then twisted as in a ring twister so that the longitudinal bonded strip forms a core with the bulked fibers extending on all sides to form a limited stretch, bulked product. The bonding of the fibers at the points of cross over imparts dimensional stability without decreasing the bulk or softness of the yarn.

The nature of the invention will be better understood from the following description, taken in connection with the accompanying drawings in which certain specific embodiments have been set forth for purposes of illustration.

In the drawings:

FIG. 1 is a vertical section illustrating one type of apparatus for carrying out the present invention;

FIG. 2 is a transverse vertical section taken on the line 22 of FIG. 1;

FIG. 3 is a section taken on the line 33 of FIG. 2 but on a larger scale;

FIG. 4 is a vertical section similar to FIG. 1 illustrating an embodiment for forming a pair of bonded longitudinal stripes;

FIG. 5 is a vertical section taken on the line 55 of FIG. 4;

FIG. 6 is a partial elevation similar to FIG. 4 illustrating a further embodiment of the invention;

FIG. 7 is a vertical section similar to FIG. 5 illustrating the use of a nozzle for effecting the bonding;

FIG. 8 is a detail of the product of the apparatus of FIGS. 1 and 6 before twisting;

FIG. 9 is a similar view of the product after twisting; and

3,472,717 Patented Oct. 14, 1969 FIG. 10 is a view similar to FIG. 8 illustrating the product of the apparatus of FIG. 4.

Referring to the drawings more in detail the invention is shown in FIGS. 1 to 3 as embodied in an apparatus wherein yarn 10 which has been previously crimped is unwound from a cop 11 or the like through a tension device 12 and is passed over guide rollers 13 through a heated tube 14 wherein the yarn is relaxed to restore the crimp as indicated at 15. If the yarn has not been stored in cop form a suflicient length of time to impart a temporary straight set the step of relaxing may be unnecessary. However for yarn such as nylon which has been crimped in a stuffer crimper, set and wound onto a cop under straightening tension it has been found that the crimp is restored by relaxing under heat while in a tensionless state.

The yarn with the crimp restored is passed onto a roll 21 which may be a silicone rubber roll. The roll 21 is driven by suitable means not shown at a rate such that the yarn remains tensionless after passing from the heating tube 14 and is flattened and spread out in a transverse layer by a fabric shield 22 composed for example of spun glass and having a liner 23 of a heat resistant low friction material such as Teflon. A wire 24 which may be heated electrically as by leads 26 extends over the fabric shield 22 and is held against the fabric by a weight 25. In this way heat is applied to a longitudinal stripe centrally of the flattened yarn on the roll 21 through the fabric shield 22 and liner 23. This heat is adapted to bind the fibers at points of cross-over along a stripe 27 as shown in FIG. 8.

From the roll 21 the yarn passes over a guide roll 31 and down through an eye 32 to a ring twister 33 of the usual type which is adapted to impart a twist to the yarn as it is wound on a spindle 34. The twisted yarn is shown in FIG. 9 wherein the bonded stripe 27 is disposed centrally as a core from which the unbonded fibers extend to form a uniformly bulked product.

The embodiment of FIGS. 4 and 5 is adapted to form a pair of spaced bonded stripes 40 along the yarn as shown in FIGS. 4 and 10. In this form the roll 21 is similar to the roll 21 of FIGS. 1 to 3. The heating is accomplished by a heating roll 41 mounted on a spindle 42 and provided with a heat source shown as a resistance rod 44 mounted within the spindle. The roll 41 carries a pair of annular flanges 45 having narrow peripheral edges which are adapted to contact the yarn as it passes over the roll 21 and apply heat to the two spaced stripes 40 for bending the same. A yarn flattening shoe 46 is disposed over the roll 21 in advance of the bite of the flanges 45. The remainder of the apparatus is similar to that above described.

The yarn having the two stripes may be twisted to form a yarn having bonded stripes on two opposite sides with the remainder of the fibers extended to form a bulked yarn.

A further embodiment is shown in FIG. 6 wherein the roll 49 is similar to the roll 41 of FIG. 4 but has a single annular flange 50 adapted to engage the yarn along a central longitudinal stripe for forming a yarn similar to that of FIG. 8.

In the embodiment of FIG. 7 the roll 21 is similar to the roll 21 above described. In this case a cover shield 51 carries a nozzle 52 which is adapted to direct a jet of liquid or gas onto the flattened yarn along a predetermined stripe or stripes. The jets may comprise hot air for heating the fibers to bonding temperature or a bonding liquid for bonding the fibers at the point of cross-over.

The flanges 45 and 50 may be patterned or the jets issuing from the nozzle 52 may be varied in a predetermined sequence so as to cause the bonded stripe or stripes to be interrupted at intervals to produce a novelty "yarn having variations in stretch characteristics and in bulk along its length. In some instances the crossovers may be bonded at spaced points only. In this way the stretch characteristics of the product may be limited to a predetermined value or the yarn may be caused to have non-stretch characteristics as desired. The invention may be applied to yarns having various types of crimp, such for example as crimps formed in a stulIer crimper, or by false twisting, or by means of an air jet, or in various other Ways known in the alt. The invention is particularly applicable to fibers formed of thermoplastic materials which can be heat softened for effecting the bonding, but may be applied to other types of fibers which may be bonded under the influence of heat and pressure, or by the use of a bonding liquid as above described. In some instances the yarns may be spun from staple fibers which have been previously crimped and treated to effect bonding as set forth herein.

Various other embodiments will be apparent to a person skilled in the art.

What is claimed is:

1. The method of making a limited stretch, bulked yarn from a bundle containing a plurality of continuous filaments having permanent crimps therein which comprises passing said bundle of crimped filaments in flattened condition through a bonding station and in said station applying a bonding agent to said filaments along a continuous longitudinal stripe which is narrower than the flattened bundle and bonding the filaments at points of cross-over along said stripe only, with the unbonded crimped filaments extending laterally on both sides of said stripe and twisting said bundle to form a bulked yarn.

References Cited UNITED STATES PATENTS 1,909,192 5/1933 Taylor 57l40 3,056,711 10/1962 Frickert 15667 3,167,845 2/1965 Claussen 57140 3,251,181 5/1966 Breen et al. 57-140 3,309,855 3/1967 Stoll et al. 57140 3,380,242 4/1968 Richmond et al. 57l40 HAROLD ANSHER, Primary Examiner W. E. HOAG, Assistant Examiner US. 01. X.R. 

